1. Field of the Invention
The present invention generally relates to a bonding wire used as a packaging wire, in particular, to a bonding wire used in semiconductor packaging process.
2. Description of Related Art
In semiconductor device packaging processes for IC, LED, SAW, a wire bonding process is often performed to electrically connect the chip to the substrate by bonding wire, which used as a signal and electrical current transmitting medium between the chip and the substrate.
The primary characteristics of a bonding wire, such as breaking load, elongation, loop, melting point, and bondability with IC chips are dependent on the materials used as the bonding wire. The performance of the packaged semiconductor device is influenced by the characteristics of the bonding wire. According to different types of chip and substrate, the adapted bonding wire has different specification.
The conventional bonding wires are usually made of pure Au material. Pure Au bonding wire has better physical properties, such as elongation and electrical conductivity. However, pure Au bonding wire inevitably leads to high cost.
Therefore, the subject of the present invention is to solve the above mentioned problem to provide a low cost bonding wire with performance comparable to pure Au bonding wire.